How advertising skepticism negatively influences or effects or decreases overall consumer based brand equity?
Please check the links and the attachment below may be they help you.
https://www.researchgate.net/publication/331991555_The_importance_of_advertising_skepticism_for_brand_extension_appeals
https://www.researchgate.net/publication/324841024_Advertising_Skepticism_Need_for_Cognition_and_Consumers'_Attitudes
I would say time is the critical factor. In a short time, there can be a negative impact but later influence should disappear. If marketers understand the market and consumer scepticism, they will react and change their approach. I have only empirical feeling that the Nordic countries have high ad scepticism and are among leaders by guerilla, buzz, social and other alternative forms of promotion. A wrong strategy has a negative impact, but not because of advertising scepticism but because of the wrong strategy. In my opinion ad scepticism erodes the brand equity of such brands which do not respect the scepticism and transfer it toward brand equity of more trustworthy communicated brands. It can change the market shares but does not mean movement toward rational consumer behaviour.
Advertising skepticism might not influence brand equity, given the company continues maintaining product quality and using other promotional tools (such as sales promotion, personal selling, trade shows, direct marketing, public relations, publicity, interactive marketing communications using digital media) in an integrated manner.
Advertising skepticism, in the first place, can be avoided by following the appropriate guidelines of message designing/framing and source selection.